U5021M-NFP Atmel, U5021M-NFP Datasheet
U5021M-NFP
Specifications of U5021M-NFP
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U5021M-NFP Summary of contents
Page 1
... Enable Output Description The digital window watchdog timer, U5021M CMOS integrated circuit. In applica- tions where safety is critical especially important to monitor the microcontroller. Normal microcontroller operation is indicated by a cyclically transmitted trigger signal, which is received by a window watchdog timer within a defined time window. ...
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... Figure 1. Block Diagram with External Ciruit OSC Reset 5 Micro- controller 2 Trigger 3 Mode 1 Wake-up Pin Configuration Figure 2. Pinning SO8 U5021M Oscillator OSC OSC Input signal conditioning Power-on POR POR reset 7 GND 1 WAKE-UP 2 TRIG MODE 3 ENA 4 State machine External 4 switching circuitry Enable Test logic ...
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... Ground, reference voltage 8 OSC RC oscillator Functional Description Supply Voltage, Pin 6 RC Oscillator, Pin 8 4756C–AUTO–09/04 The U5021M requires a stabilized supply voltage V trical characteristics. An external buffer capacitor may be connected between pin 6 and GND. The clock frequency, f, can be adjusted by the components R formula where ...
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... Figure 4. Power-on Reset and Switch-over Mode VDD Reset Out Mode Supply Voltage Monitoring, Pin 5 Switch-over Mode Time, Pin 3 U5021M 4 = 500 During ramp-up of the supply voltage and in the case of supply-voltage drops the inte- grated power-on reset (POR) circuitry sets the internal logic to a defined basic status and generates a reset pulse at the reset output, pin 5 ...
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... As soon as a wake-up signal at the wake-up input (pins 1) is detected, the long watchdog mode ends, a reset pulse wakes-up the sleeping microcontroller and the normal monitoring cycle starts with the mode switch-over time. U5021M , (enable time ...
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... V DD Reset out Mode Trigger Enable Figure 7. Pulse Diagram of the Long Watchdog Time Reset out Wake-up Mode Trigger Enable U5021M Figure 7 shows the switch-over from the short to the long watchdog mode. The wake-up signal during the enable time activates a reset pulse The watchdog can be switched back from the long to the short watchdog mode with a low potential at the mode pin (pin 3) ...
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... Short window disable state time out t 2 trg_ok = 1 mode = 1 Short window enable state time out t 3 trg_err = 1 time out wedge = 1 mode = 1 Long window disable state mode = 0 time out t 4 trg_ok = 1 mode = 0 Long window enable state trg_err = 1 trg = 0 or wedge = 1 U5021M 7 ...
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... RST Inputs Logical “high” Logical “low” Hysteresis Input voltage range Input current Input current Outputs Maximum output current Logical output “low” I OUT Logical output “high” I OUT Leakage current V OUT U5021M 8 Symbol OUT amb T stg Symbol R thJA Pin ...
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... Short watchdog window Disable time Long watchdog window Enable time Long watchdog window Reset-out time Note: 1. Frequency deviation also depends on the tolerances of the external components Ordering Information Extended Type Number U5021M-NFP Package Information Package SO8 Dimensions in mm 4756C–AUTO–09/04 Pin = 470 pF ...
Page 10
... Changes from Rev. 4756B-AUTO-07/04 to Rev. 4756C-AUTO-09/04 U5021M 10 Please note that the following page numbers referred to in this section refer to the specific revision mentioned, not to this document. 1. Electrical Characteristics Table, page 8, row “Reset capability” added 1. Electrical Characteristics Table, page 8, row “Reset capability” changed in “ ...
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... No licenses to patents or other intellectual property of Atmel are granted by the Company in connection with the sale of Atmel products, expressly or by implication. Atmel’s products are not authorized for use as critical components in life support devices or systems. ...